Process of making soluble alkaline silicates.



IUMTED STATES",

irm owes FRITZ HENKEL, oF DUss LDoRr, G RMANY.

PROCESS OF fMAKlN G SOLUBLE, ALKALlNE SILIQATTESQ sracxrroatrron aimi part of Letterslatent'ltor 633,841, dated September 26, 1899; Application filed Tune 15,1893. seri iuacsatos. (NospeoimensJ I V To atZZ whom it may concern:

'Be it known that Fmrz HENK'uL-,"a ub jectoffthe King of Prussia,Emperor'o'fGermany, residing at Dusseldorf,- in the Kingdom of Prussia and German Empire, have in Vented certain new and useful Improvemen ts in Processes forthe Manufacture of Solid but Easily Soluble'Alkaline silicates, (for which I have applied for patentsin England-April 27, .1898,' No. 9,730; in Austria May i, 1898; in Hungary May3- l898, No. 6,2895'inl3rant3e April 28, 1.898, No. 265,241; in Belgium April 27,1898xNo. 105,6ll,and in Spain April 26,,

|189,8,) of which the followingzis alspecifica tion. t V This invention relates to the manufacture of concentrated silicie alkali or alkaline silicats in the form of powderior pieces, easilysoluble in cold watelgwhich manufacture has hitherto been attempted without success.

This processis based upon the observation that by intimately mixing solid silicic alkali or alkaline silicate with a little water in the proportion of about six to one and strongly heating the mixture, or by mixing the solid silicic alkali or alkaline silicate with a hot concentrated. solution of the silicate, a substance is obt-ainedwhich cakes together to forma solid mass which can be pulverized and iseasily soluble in cold water. During the application of water the solid insoluble .silicic alkali or alkaline silicate absorbs the v water mechanically without alteration of its properties, specially as regards'insolubility; but when the mixture isstrongly heated a chemical change takes place between the insoluble particles of the water-glass and the particles of water in contact therewith. Crystalline hydrate is thus formed which can be finely pulverized andwhichis easily soluble in water. By the application of a hot concentrated solution of the silicate thesolution of silicate is transformed into a solid aggregate body withoutthe silicate losing any of its easy solubility,'and, further, the solid silicate which was previously insoluble in cold water is sim ultaneously changed into the sol uble form by interchange with theparticles of i the concentrated solution.

' The process is carried out in practice as fol- ;low's,ias an example:

f First. Six parts of silicate of sodium or po tassifum, as it is obtained from the furnace and containing more or less alkali, are pul- Iverized, intimately mixed with one part of water, and the mixture is then strongly heated at a temperatureof 100 tol20 centigrade fora short time until thewater has disapi peared and a homogeneous-substance'is 010- I tained,'.which cakes to form a solid mass.

The product thus obtained is easily soluble in cold water and may be disintegrated or pulverized.

Second. as obtained from the furnace and containing more or ,less'sodin m or potassium, is dissolved by means of hotwater or steam, With this hotsolution powdered sodium water-glass or powdered potassium water-glass is mixed, and this mixture is allowed to cool. -The mixturebecomes solid in very short time and forms a hard cake, which maybe disintegrated or pulverized, according to requirement. c 7' Other substances-for instance, such as no in'jurious effect onthe use of the mixture Silicate of sodium or-potassium,

, sawdust, peat, turf, or magnesia which have may be added as a loosening agent when the product is to be used as a fertilizer either during the disintegration or manufacture.

This process allows of easy transportation of the material and saves freightand customs duties, because the product is a concentrated solid silioate easily soluble. The product is to be used especially in the manufacture of silicatemanure in dry condition suitable for strewing.

What I claim, and desire to secure by Let ters Patent of the United States, is-= 1. The herein-described process for treatinglalkaline silicates, which consists in mix ing six parts of a solid alkaline silicate with one part of water, and strongly heating the mixture until the water has disappeared and a homogeneous mass is formed, which mass cakes and is then easily soluble in cold water,

, 2. The herein-described process of treatin g alkaline silicates which consists in heat- In testimony whereof I have hereunto set my hand in the presence of two Witnesses.

FRITZ HENKEL.

\Vibnesses:

WILLIAM EssENWEIN, W. B. PETTIT.

finally allowing the mixture to cool and cake whereby it is rendered easily soluble in cold Water. 

